On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote: > If the module requires only one clocksource to function, then > driver can very well call clk_get() api with "con_id = NULL", > > clk = clk_get(dev, NULL); > > And platform code should respect this and return valid clk handle. > That means, now the clk_get() api would rely on dev_id, and platform > code should either have clk node with matching dev_id (with con_id=NULL) > or return dummy clk node. > > With DT support, we can fix the dev_id for particular module > using "struct of_dev_auxdata" to satisfy above clk framework requirement. > > In case of AM33XX, we required this for the DCAN module, so this > patch adds "of_dev_auxdata" for both DCAN_0/1 instances. > > Signed-off-by: Vaibhav Hiremath <hvaibhav@xxxxxx> > Cc: Tony Lindgren <tony@xxxxxxxxxxx> > Cc: Paul Walmsley <paul@xxxxxxxxx> > Cc: Benoit Cousson <b-cousson@xxxxxx> > Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> > --- > This patch is boot tested on BeagleBone platform, and checked for > clk_get() return value in d_can module driver. > > arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++- > 1 files changed, 17 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c > index 6f93a20..c9b7903 100644 > --- a/arch/arm/mach-omap2/board-generic.c > +++ b/arch/arm/mach-omap2/board-generic.c > @@ -37,11 +37,27 @@ static struct of_device_id omap_dt_match_table[] __initdata = { > { } > }; > > +/* > + * Lookup table for attaching a specific name and platform_data pointer to > + * devices as they get created by of_platform_populate(). Ideally this table > + * would not exist, but the current clock implementation depends on some devices > + * having a specific name OR to satisfy NULL con_id requirement from driver. > + */ > +static const struct of_dev_auxdata am33xx_auxdata_lookup[] __initconst = { > + OF_DEV_AUXDATA("bosch,d_can", 0x481cc000, "d_can.0", NULL), > + OF_DEV_AUXDATA("bosch,d_can", 0x481d0000, "d_can.1", NULL), > + { }, > +}; Adding an additional clkdev lookup accomplishes the same thing and is a cleaner solution. Rob > + > static void __init omap_generic_init(void) > { > omap_sdrc_init(NULL, NULL); > > - of_platform_populate(NULL, omap_dt_match_table, NULL, NULL); > + if (of_machine_is_compatible("ti,am33xx")) > + of_platform_populate(NULL, omap_dt_match_table, > + am33xx_auxdata_lookup, NULL); > + else > + of_platform_populate(NULL, omap_dt_match_table, NULL, NULL); > } > > #ifdef CONFIG_SOC_OMAP2420 > -- > 1.7.0.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html